Statute Miles and Nautical Miles
Date: 5/11/96 at 23:15:28 From: Anonymous Subject: Statute Miles and Nautical Miles Could you please tell me the difference between statute miles and nautical miles? Why do they use statute miles for space shuttle launches rather than miles per hour?
Date: 12/11/96 at 01:04:19 From: Doctor Rob Subject: Re: Statute Miles and Nautical Miles A mile was originally 1000 ("mille" in Latin) paces of a Roman soldier. In latter years it has been standardized at 5280 feet. Since the standardization was accomplished by law, it is more formally known as a statute mile. The nautical mile has varied in the past. It is supposed to be the length of one minute of arc at the equator. The actual value has been 6080 feet, 6080.20 feet, but now it is standardized at 6076.103 feet. It is called a nautical mile because sailors have been using it for many, many years. This is due to the use of spherical trigonometry in navigation. They probably use the phrase "statute miles" for space shuttle launches to make sure that everyone understands that these are not nautical miles, which is what the navy tends to use, but rather the more common kind that most people are familiar with from their cars' speedometers and odometers. -Doctor Rob, The Math Forum Check out our web site! http://mathforum.org/dr.math/
Date: Nov. 16, 1998 From: Michael Young In an answer to a question sent to you in 1996 you discussed the difference between the statute mile and the nautical mile. The value you gave for the current length of the nautical mile is not strictly correct. The length you gave (6076.103 Feet) is based on what are now called U.S. Survey Feet. Because of a growing divergence in the definitions of English Units used in the major English speaking countries they got together in 1958 to establish common standards for the inch-pound measurement system in terms of metric units. The International Yard was established as 0.9144 metres exactly. The United States officially adopted this value in 1959 (See Federal Register, Vol 24, No 123, P 5348). As a result of this new definition of the yard the length of a Nautical Mile, while still 1852 Metres, changed to 6076.11549 International Feet.
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